Surgical tool for cutting plaster casts



Aug. 12, 1941. E. E. LONGFELLOW SURGICAL TOOL FOR CUTTING PLASTER CASTSFiled June 18, 1940 INVENTOR.

ATTORNEY Patented Aug. 12, 1941 a Application June is, 1940, Serial No.341,195

" eams. ;(.01 30 -194) This invention relates to surgical tools forcutting plaster casts While in place on a patient for the purpose of itsremovaL l I K An object of the invention is to providea cuttinginstrument that isapplied to'a plaster cast 3 by which an opening ismade through the' wall of the castfrom one end to thei'other withdutliability fof icausing injury orrdiscomfor-t to the patient. f

Another object of the invention is to afford a cutting instrument'for'plaster casts that operates expeditiously and effectively whereforeremoval of the cast is accomplished with dispatch and with but littleexertion upon the part of the operator.

And a further object of the invention is to construct a tool capable ofcutting through the wall of a plaster cast in such manner as to leavebut little debris resulting from the kerf made by the tool.

Other objects and advantages of the invention appear in the followingdescription.

An illustrative embodiment of the invention is shown in the accompanyingdrawing, in which- Fig. 1 is a fragmentary side elevational view of astructure in which the invention is incorporated, a portion thereofbeing in section;

Fig. 2 is a fragmentary front elevational view of thestructure shown inFig. l, with the operating lever in elevated position, and a portion insection in a vertical plane indicated in Fig. 1 by the dotted line 2;and

Fig. 3 is a cross-sectional view projected from Fig. 1, the sectionbeing on the line 3-3 thereof.

The illustrative embodiment of the invention consists of a handle Ihaving a head 2 at one end thereof provided with a rigid pendent jaw 3.A forwardly projecting extension 4 of the jaw has made therein a dieopening 5 in which is received a punch 6 that extends up through thehead 2 and has sliding movement therein.

An operating lever 1 is provided having a forked end 8 that is disposedastride of the head 2, and is connected therewith by a pivot 9 at apoint therein ahead of the punch 6. A driving pin H1 is secured in thearms of the fork 8 and extends loosely through an arcuate slot II in thehead and also through an elongated slot l2 in the punch so that when theoperating lever I is raised or lowered corresponding movement thereby isimparted to the punch.

The lower end of the punch preferably is shaped to have a series ofoffsets 13 that extends from the front of the punch diagonally downwardto the lowermost extremity thereof. The

end of the punch -havingtlie offsets is adapted tobe projected partwaythroughthe die opening 5 in the jaw extension," and theb ack edge of thepunch bears constantly' against the adjacent edge of the jaw 3*upo'h'whichit has sliding move ment. The bottom of'thejaw has made therein alongitudinal groove constituting a throat' l4 wherefore to permitdischarged material removed from the cast upon operation of the punch;The top, sides, bottom and the forward end of thejaw" exten'sionissmoothly rounded so as to facilitate its introduction between the castand the body of the patient.

In using the tool, the lever l is raised so that the punch is elevatedto its uppermost position, the projecting end of the extension 4 of thejaw is then inserted between the inner wall of the plaster cast to'beremoved (not shown) and the flesh of the patient adjacent thereto, andwhile thus positioned the operating lever is forced downwardly by theoperator which causes the punch to bear upon the exterior wall of thecast with the effect that the immediate end portion of the cast ispunched through the die opening 5 into the throat M of the jaw, and alsothat portion of the cast immediately ahead of the punched portion of thecast is broken down by pressure of the forward succession of offsets ofthe punch. The pendent rear portion of the jaw 3 preferably is of lesslateral thickness than the punch so that upon each punching operationthe tool may readily be advanced further into the cast without hindranceof the jaw. Upon elevation of the operating lever and consequent raisingof the punch the tool is then advanced into a secondary position so thatupon again moving the operating lever downward the punching and breakingdown operations are repeated. As the tool is further advanced thepunchings removed from the cast are left in the wake of the advancingjaw out of the way from interference with the progress of the tool.These operations are continued until the tool shall have traversed theentire length of the cast or about that portion thereof desired to beremoved from place.

Upon each operation of the lever that portion of the cast that isdisposed beneath the rear portion of the punch is completely severed anddisposed of by the punch into the throat, and the immediate precedingadjacent portion of the cast is crushed down which permits subsequentmovement thereof to position beneath the rearmost die-penetratingoffsets of the punch as the tool is advanced and operated.

Variations from the particular construction above disclosed may readilybe made by exercise of engineering skill without departure from thespirit or scope of the invention, and the following claims are intendedto be inclusive of such variations.

What I claim is:

1. In a cutting tool for plasterrcasts, a handle having a head at oneend thereof provided with a rigid pendent jaw, there being a die openingformed in a forwardly projecting extension of said jaw and alongitudinal throat in the bottom thereof, a punch having slidingmovement in said head, its lower end being shaped to have a series ofoflsets extending from the front of the punch diagonally downwardthrough said die opening when the punch is in lowermost position, anoperating lever having a forked end disposed astride of said head andpivotally connected thereto, and adrive pin in connection with saidlever extending through slots in said head and punch wherefore saidpunch is actuated upon operation of said lever.

2. A cutting tool. for plaster casts having a handle provided with ahead, a jaw in connection with the head having a forwardly projectingextensionprovided with a die opening therein and a longitudinal throatin its bottom, and a punch, provided with means to reciprocate it,movable in said head, and the lower end of which has offsets disposed ina series extending diagonally downward from the front of the punch, arearmost portion of said offsets having shearing relation with saidextension upon movement thereof through said die opening.

3. ,A cutting tool for plaster casts consisting of a head including ajaw with a forwardly projecting extension having a die opening thereinand a longitudinal throat in the bottom of said extension communicatingwith the die opening, and a punch provided with actuating means thereforand having a series of offsets in one end disposed diagonally downwardfrom the front thereof, the rearmost of said offsets having shearingrelation through said die opening with said extension and theforwardmost of said extensions having crushing relation with the wall ofa plaster cast when said cast is inserted between said punch and saidextension upon operation of said punch.

4. In a tool for removing surgical plaster casts, a head provided with apendant jaw and extension thereof, said extension having a die openingtherein, a punch having guided movement in said head, one end of saidpunch having a diagonal series of offsets the lowermost of which entersaid die opening upon movement of the Punch to the end of itsdownstroke, and an operating member pivoted on said head and havingactuating engagement with said punch EARL E. LONGFELLOW.

